SFH 313 FA - 

Phototransistor T-1 3/4 (5mm) Package
This family of NPN silicon phototransistors, from OSRAM Opto Semiconductors, are a range of 5mm (T-1 3/4) through-hole devices. They have both clear or black plastic lenses, the diffused lenses being used for daylight filters. Suitable applications include; computer-controlled flashes, photointerrupters, industrial electronics and for control/drive circuits.